POY (Polyester Pre-Oriented Yarn) oil agent formula for reducing small stiff yarns of nylon-6 high stretch yarns and application thereof

Abstract

The invention belongs to the field of chemical fiber production, and discloses a POY (pre-oriented yarn) oil agent formula for reducing small stiff yarns of nylon-6 high stretch yarns and application of the POY oil agent formula. According to the oiling agent, fatty acid pentaerythritol ester is used as a smoothing agent, and the weight ratio of the fatty acid pentaerythritol ester is controlled to be 35-40%; fatty alcohol-polyoxyethylene ether is used as an emulsifier, polyether phosphate salt is used as an antistatic agent, and a softening agent SG is used as a softening agent. The content of the smoothing agent is reduced in the POY oiling link, so that the friction force is increased and the operation is stable in the draw texturing process, the reduction rate of small stiff yarns of DTY is reduced from 18.2% to 0%, the rate of superior products is improved by about 15%, and meanwhile, the indexes such as the breaking strength, the elongation and the yarn unevenness of fibers still meet the requirements of GB / T 16603-2008. The process is simple, equipment does not need to be transformed, and the process is suitable for industrial production of the chinlon 6 high stretch yarn.

Description

Technical Field

[0001] This invention belongs to the field of chemical fiber production and relates to a POY oiling agent formulation for reducing small stiff filaments in nylon 6 high-elasticity yarn and its application. Background Technology

[0002] Nylon, due to its excellent physical properties such as high strength, good moisture absorption, and vibrant dyeing characteristics, is widely used in the apparel industry. In recent years, research on the production of nylon 6 (polycaprolactam, PA6) fiber, particularly on improving product quality, has been ongoing. Nylon 6 high-elastic yarn, due to its high strength, high resilience, fatigue resistance, and excellent dyeing properties, is widely used in high-end sportswear, swimwear, underwear, and automotive interiors. As end-market demands for fabric appearance quality and dyeing uniformity continue to increase, the "zero-defect" requirement for nylon 6 DTY (Draw Textured Yarn) is becoming increasingly stringent. However, in actual industrial production, traditional nylon 6 fiber is prone to water absorption and deformation after cold stretching. During texturing, the multifilaments are prone to sticking together, which easily leads to a defect known as "micro-tightspots". Specifically, it manifests as excessive local tension in one or several filaments, resulting in stiffness and whitening, forming obvious color streaks and spots on the fabric. In severe cases, it can cause the entire batch of fabric to be downgraded and scrapped, resulting in dyeing spots and uneven dyeing when producing products in the high-end weaving field.

[0003] The formation mechanism of small, stiff filaments is as follows: nylon 6 chips are melted, spun, and wound to obtain POY (Pre-Oriented Yarn). POY requires multiple processes on a texturing machine, including high-temperature stretching, false twisting, and setting, to obtain high-elasticity yarn. During this process, the filament frequently rubs against metal surfaces such as guide hooks, hot rollers, false twisters, and cooling plates. If the smoothing properties imparted by the POY surface oil are too high, the dynamic friction coefficient between the filament and the metal is too low, making the filament prone to vibration and slippage. When local speed differences accumulate, a "tight spot" forms at the exit of the false twister, eventually solidifying into small, stiff filaments. Statistics show that with traditional POY oil containing 55% smoothing agent, the rate of small, stiff filament degradation can reach as high as 18-19% during the low-temperature and low-humidity season from November to February of the following year, becoming a bottleneck restricting the quality improvement of high-value-added nylon 6 DTY.

[0004] Existing technologies for treating small, stiff fibers in nylon 6 high-elasticity yarn mainly focus on three aspects: process parameters, equipment structure, and oiling agent formulation. However, all of these methods have significant limitations. (1) At the process level, by increasing the DTY draw ratio, reducing the twist ratio, or lowering the temperature of the hot box, only minor adjustments can be made at the edge of the tribodynamics. These adjustments cannot fundamentally change the rapid accumulation of filaments at the exit of the false twister, and the rate of downgrading of small stiff filaments remains at 17-19%. (2) At the equipment level, although replacing the imported anti-twist device or optimizing the guide wire path can reduce the sudden change in local tension, the modification cost is high and the machine needs to be shut down for modification, which is difficult to popularize on existing high-speed production lines. (3) Regarding the oiling agent, simply reducing the oil content of POY will lead to an increase in the breakage rate of the filament bundle; some industry professionals have replaced the fatty acid pentaerythritol ester with fatty acid xylitol ester, but due to surface tension and compatibility issues, the improvement of small stiff filaments is insufficient; when trying to reduce the proportion of smoothing agent, the oiling agent will experience phase separation, increased foaming, and uneven oiling, which seriously affects the stability of continuous spinning. Therefore, the existing technology has never been able to meet the comprehensive needs of "reducing small stiff filaments, production stability, and cost control", forming a pain point in the long-term development of the industry. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention aims to provide a POY oiling agent formulation and its application method for reducing small stiff fibers in nylon 6 high-elasticity yarn, so as to achieve a POY oiling agent improvement scheme that requires no equipment modification, has low cost, and strong process compatibility, thereby reducing small stiff fibers and maintaining fiber mechanical properties and production stability.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a POY oiling agent formulation for reducing stiffness in nylon 6 high-elasticity yarn, comprising the following components by weight percentage: smoothing agent 35-40%, emulsifier 20-24%, antistatic agent 3%, softening agent 19-20%, and other auxiliaries 18%.

[0007] Preferably, the smoothing agent is a pentaerythritol fatty acid ester.

[0008] Preferably, the emulsifier is fatty alcohol polyoxyethylene ether.

[0009] Preferably, the antistatic agent is a polyether phosphate salt.

[0010] Preferably, the softening agent is softener SG.

[0011] This invention applies a POY oiling agent formulation that reduces stiffness in nylon 6 high-elasticity yarn to the production of nylon 6 high-elasticity yarn.

[0012] The present invention also provides a method for producing nylon 6 high-elasticity yarn, specifically including the following steps: (1) Polycaprolactam chips were melted and spun using a screw extruder to obtain POY 85D / 24F precursor yarn; (2) In the POY oiling process, a POY oiling agent formula that reduces the stiffness of nylon 6 high elastic yarn is used. The oiling process is carried out through two wet oiling systems and the oiling rate is controlled. (3) The oil-containing POY is texturized by the high elastic yarn texturizing machine, and after passing through the filament cutter, it enters the first roller, then passes through the heating box and is false twisted in the false twister. After passing through the second roller, it enters the second heating box, and finally is wound by the winding tension. The draw ratio and twist ratio are adjusted, and the untwisting tension is controlled to be 26-28 CN to obtain high elastic yarn 70 D / 24 F. (4) The high elastic yarn 70 D / 24 F was subjected to quality inspection to determine the rate of degradation of small stiff yarns in the high elastic yarn.

[0013] Preferably, in the method for producing nylon 6 high elastic yarn, the oiling rate in step (2) needs to be controlled at 0.6% ± 0.1%.

[0014] Preferably, in the method for producing nylon 6 high-elastic yarn, the false twister temperature in step (3) is 168°C; the draw ratio is 1.25; and the twist ratio is 1.62.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Traditional processes using high-smoothing agent formulations (typically ≥55%) result in insufficient friction on the yarn path during DTY texturing. This causes abnormal vibration of the yarn during high-speed operation, leading to abnormal contact with the yarn guide and the formation of stiff yarns, resulting in a product downgrade rate as high as 18%. This invention unexpectedly and innovatively reduces the smoothing agent ratio to 40%. By reducing excessive lubrication on the yarn surface, the untwisting tension is significantly increased from the traditional 16-19 CN to 26-27 CN. This increased friction effectively suppresses yarn slippage within the texturing machine, fundamentally blocking the path to stiff yarn formation and verifying the mechanism that increased friction reduces small stiff yarns. Large-scale production verification shows that the downgrade rate of small stiff yarns can be reduced to 0%. Feedback from downstream weaving mills consistently confirms that the dyeing uniformity of the woven fabric is significantly improved, completely eliminating quality problems such as cloudiness and uneven coloring.

[0016] 2. The industry has long held the technical bias that "high lubricant content improves processing performance," generally believing that increasing lubricant content reduces breakage rate and maintains stable performance. This invention, for the first time through systematic testing, demonstrates that reducing the lubricant ratio to 40% can completely eliminate small, stiff yarn defects without altering physical properties. The 40% lubricant content serves as a critical threshold, significantly exceeding industry expectations. This solution directly reduces lubricant usage (from 55% to 40%), lowering oiling raw material costs. More importantly, it exhibits extremely high process adaptability—while maintaining the synergistic effect of core components such as emulsifiers and antistatic agents, it can be directly applied to existing POY-DTY continuous spinning production lines without modifying texturing equipment or adjusting complex parameters such as temperature and draw ratio, significantly reducing investment in technological upgrades.

[0017] 3. This invention reduces the number of stiff nylon 6 high-elasticity yarns by deeply synergizing the oiling agent components and processing technology: a stable combination of pentaerythritol fatty acid ester (35-40%) and fatty alcohol polyoxyethylene ether (20-24%) is formed, which increases the dynamic friction coefficient of the yarn while reducing the amount of lubricant used, forcing the untwisting tension to jump to 26-28 CN; the characteristics of this oiling agent are coupled with the two-stage wetting and oiling process to completely suppress yarn vibration and slippage, reducing the rate of downgraded stiff yarns from 18.2% to zero, increasing the rate of superior products by 15%, and ensuring that the fiber properties fully meet the standards; moreover, the cost of oiling agent is reduced with zero equipment modification cost, forming an inseparable synergistic closed loop of "critical component ratio - process tension threshold - leap in quality of the industrial chain".

[0018] 4. While completely solving the problem of small, stiff fibers, the nylon 6 high-elastic yarn produced by this invention fully maintains its excellent physical properties. After rigorous testing, key indicators such as fiber breaking strength, boiling water shrinkage rate, and yarn evenness all meet the requirements of the national standard GB / T16603-2008 "Nylon Elastic Yarn," satisfying the stringent standards for raw materials in the high-end weaving industry. This not only eliminates problems such as fabric degradation caused by dyeing spots but also significantly improves the quality of finished textiles, reducing quality loss costs for downstream customers and forming a positive quality cycle throughout the entire chain from spinning to weaving. Attached Figure Description

[0019] Figure 1 The production process of nylon filament POY as described in Example 1 is as follows: 1. Chips; 2. Hopper; 3. Storage tank; 4. Transmission gearbox speed change mechanism; 5. Screw extruder; 6. Melt pipe; 7. Metering pump; 8. Spinning assembly; 9. Wet and oil device (first stage); 10. Filament cooling device; 11. Wet and oil device (second stage); 12. Pre-networker; 13. Guide bar; 14. Main networker; 15. Hot roller box; 16. Winding guide hook; 17. Winding head, where ①-⑤ are rollers 1-5. Detailed Implementation

[0020] The present invention will be further described below with reference to preferred embodiments. The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values. These ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed herein.

[0021] Unless otherwise specified, the experimental methods in the following embodiments are conventional methods, performed in accordance with the techniques or conditions described in the literature in this field or in accordance with the product instructions.

[0022] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0023] Example 1 This embodiment provides a POY oiling agent formulation for reducing small stiff fibers in nylon 6 high-elasticity yarn, comprising the following components by weight percentage: 40% smoothing agent, 20% emulsifier, 3% antistatic agent, 19% softening agent, and 18% other additives.

[0024] In this embodiment, the smoothing agent is a pentaerythritol fatty acid ester; the emulsifier is a fatty alcohol polyoxyethylene ether; the antistatic agent is a polyether phosphate salt; and the softening agent is softener SG.

[0025] In this embodiment, the post-treatment of the POY oil agent that reduces the stiffness of nylon 6 high-elasticity yarn is to pump the oil agent into the oil storage tank until the liquid level reaches the required scale value. In order to increase the dispersibility and uniformity of the oil agent and reduce the generation of oil agent foam, the injection speed is controlled at 25~35 min. The water temperature of the constant temperature water tank is maintained at M±0.5℃ (25≤M≤30M value is determined according to the instrument requirements), and the mixture is stirred for 80±10 min. The concentration is calibrated online using an Abbe refractometer.

[0026] In this embodiment, the above-mentioned POY oiling agent formula for reducing stiff nylon 6 high-elasticity yarn is used as the oiling agent for the production of nylon 6 high-elasticity yarn. The preparation method for producing nylon 6 high-elasticity yarn includes the following steps: (1) such as Figure 1 As shown, polycaprolactam chips are melted in a screw extruder with five temperature zones set to 255℃, 256℃, 257℃, 258℃, and 260℃, forming polyamide 6 melt. After being precisely metered by a metering pump, the melt is extruded through a spinning assembly and a spinneret to form nascent fibers. The spinning speed is controlled at 4200 m / min to obtain POY 85D / 24F precursor yarn. (2) In the POY oiling process, an oiling agent formula that reduces the stiffness of nylon 6 high elastic yarn is used. The oiling process is carried out through two wet oiling systems, and the oiling rate is controlled at 0.6% ± 0.1%. (3) The oil-containing POY is texturized by a DTY texturizer at a speed of 680 m / min. After passing through the shredder, it enters the first roller (FR1), then passes through a heating box at 168℃ and undergoes false twisting in a false twister. After passing through the second roller, it enters the second heating box and is finally wound by winding tension to obtain DTY 70 D / 24 F, in which the draw ratio is 1.25 and the twist ratio is 1.62. (4) The quality of appearance indicators of the obtained DTY 70 D / 24 F is tested to determine the rate of degradation of small stiff fibers in the tested DTY.

[0027] In this embodiment, the untwisting tension of the produced yarn is 26-27 CN after texturing by a texturing machine. The degradation rate of DTY small stiff yarn after quality inspection is 0%. At the same time, physical property tests were carried out. The breaking strength, breaking elongation, yarn unevenness, boiling water shrinkage rate and other indicators of the obtained nylon 6 fiber all meet the specified range of GB / T16603-2008 "Nylon Elastic Yarn" and can meet the requirements of post-processing and use.

[0028] Example 2 This embodiment provides a POY oiling agent formulation for reducing small stiff fibers in nylon 6 high-elasticity yarn, comprising the following components by weight percentage: 35% smoothing agent, 24% emulsifier, 3% antistatic agent, 20% softening agent, and 18% other additives.

[0029] In this embodiment, the smoothing agent is a pentaerythritol fatty acid ester; the emulsifier is a fatty alcohol polyoxyethylene ether; the antistatic agent is a polyether phosphate salt; and the softening agent is softener SG.

[0030] In this embodiment, the post-treatment method of the POY oiling agent for reducing the stiffness of nylon 6 high-elasticity yarn is the same as that described in Embodiment 1 above, and will not be repeated here.

[0031] In this embodiment, the steps of using the POY oiling agent formulation described above to reduce the stiffness of nylon 6 high-elasticity yarn in the production of nylon 6 high-elasticity yarn are the same as those described in Embodiment 1 above, and will not be repeated here.

[0032] In this embodiment, the untwisting tension of the produced yarn is 27-28 CN after texturing by a texturing machine. The degradation rate of DTY small stiff yarn after quality inspection is 0%. At the same time, physical property tests were carried out. The breaking strength, breaking elongation, yarn unevenness, boiling water shrinkage rate and other indicators of the obtained nylon 6 fiber all meet the specified range of GB / T16603-2008 "Nylon Elastic Yarn" and can meet the requirements of post-processing and use.

[0033] Comparative Example 1 This comparative example provides a POY oiling agent formulation for reducing small stiff fibers in nylon 6 high-elasticity yarn, comprising the following components by weight percentage: 55% smoothing agent, 15% emulsifier, 3% antistatic agent, 13% softening agent, and 14% other auxiliaries.

[0034] In this embodiment, the smoothing agent is a pentaerythritol fatty acid ester; the emulsifier is a fatty alcohol polyoxyethylene ether; the antistatic agent is a polyether phosphate salt; and the softening agent is softener SG.

[0035] In this comparative example, the post-treatment method for the POY oiling agent formulation for reducing small stiff nylon 6 high-elasticity yarns is the same as that described in Example 1 above, and will not be repeated here.

[0036] In this comparative example, the steps of using the POY oiling agent formulation described above to reduce the stiffness of nylon 6 high-elasticity yarn in the production of nylon 6 high-elasticity yarn are the same as those described in Example 1 above, and will not be repeated here.

[0037] In this comparative example, the untwisting tension of the produced yarn after texturing by a texturing machine was 16-19 CN. The downgrade rate of DTY stiff yarn after quality inspection was as high as 18.2%. Physical property tests were conducted, and the breaking strength, breaking elongation, yarn unevenness, boiling water shrinkage rate and other indicators of the obtained nylon 6 fiber all met the specified range of GB / T16603-2008 "Nylon Elastic Yarn" and could meet the requirements of post-processing and use.

[0038] To verify the POY oil formulation of Example 1 after optimizing and reducing the lubricant content, the following physical indicators were compared between Example 1 and Comparative Example 1. Table 1

[0039] In the production process of nylon filament, after the weight ratio of lubricant in the oil was reduced from 55% to 40%, the decrease in linear density deviation and yarn unevenness fully verified the core advantage of this invention, which suppresses shaking and slippage due to increased yarn friction, thereby eliminating small stiff yarns. In terms of core physical indicators, the 40% lubricant formula is not substantially different from the traditional solution. Under the premise of maintaining the basic physical properties of the fiber, this formula significantly improves the uniformity of the product and the stability of processing.

[0040] Comparative Example 2 This comparative example provides a POY oiling agent formulation for reducing small stiff fibers in nylon 6 high-elasticity yarn, comprising the following components by weight percentage: 55% smoothing agent, 15% emulsifier, 3% antistatic agent, 13% softening agent, and 14% other auxiliaries.

[0041] In this embodiment, the smoothing agent is a fatty acid xylitol ester; the emulsifier is a fatty alcohol polyoxyethylene ether; the antistatic agent is a polyether phosphate salt; and the softening agent is a softener SG.

[0042] In this comparative example, the post-treatment method for the POY oiling agent formulation for reducing small stiff nylon 6 high-elasticity yarns is the same as that described in Example 1 above, and will not be repeated here.

[0043] This comparative example utilizes the POY oiling agent formula described above for reducing stiffness in nylon 6 high-elasticity yarn, applied to the production of nylon 6 high-elasticity yarn. The specific steps are as follows: (1) Polycaprolactam chips are melted by a screw extruder with five temperature zones set to 255℃, 256℃, 257℃, 258℃ and 260℃ respectively to form polyamide 6 melt. After being accurately metered by a metering pump, it is extruded through a spinning assembly and a spinneret to form nascent fibers. The spinning speed is controlled at 4200 m / min to obtain POY 85D / 24F precursor yarn. (2) In the POY oiling process, an oiling agent formula that reduces the stiffness of nylon 6 high elastic yarn is used. The oiling process is carried out through two wet oiling systems, and the oiling rate is controlled at 0.6% ± 0.1%. (3) The oil-containing POY is texturized by a DTY texturizing machine at a speed of 680 m / min. After passing through the shredder, it enters the first roller (FR1), then passes through a heating box at 173℃ and undergoes false twisting treatment in a false twister. After passing through the second roller, it enters the second heating box and is finally wound by winding tension to obtain DTY 70 D / 24 F, in which the draw ratio is 1.62 and the twist ratio is 1.83. (4) The quality of appearance indicators of the obtained DTY 70 D / 24 F is tested to determine the rate of degradation of small stiff fibers in the tested DTY.

[0044] In this comparative example, the untwisting tension of the produced material after texturing was 16-19 CN, and the downgrade rate of DTY stiff yarn after quality inspection was as high as 25%. The results show that even if the composition of the oiling agent formula is changed and conditions such as draw ratio, twist ratio and hot box temperature are optimized, the downgrade rate of stiff yarn cannot be improved by maintaining the industry-standard high smoothing agent formula. This confirms that the traditional high smoothing agent formula is the main factor in the existence of stiff yarn, and even with process fine-tuning, the bottleneck of stiff yarn cannot be overcome. In this invention, the unexpected discovery of reducing the smoothing agent content overcomes the industry's technical bias of over-reliance on high smoothing agents to maintain "theoretical stability".

[0045] Comparative Example 3 This comparative example provides a POY oiling agent formulation for reducing small stiff fibers in nylon 6 high-elasticity yarn, comprising the following components by weight percentage: smoothing agent 45%, emulsifier 19%, antistatic agent 3%, softening agent 17%, and other auxiliaries 16%.

[0046] In this embodiment, the smoothing agent is a pentaerythritol fatty acid ester; the emulsifier is a fatty alcohol polyoxyethylene ether; the antistatic agent is a polyether phosphate salt; and the softening agent is softener SG.

[0047] In this comparative example, the post-treatment method for the POY oiling agent formulation for reducing small stiff nylon 6 high-elasticity yarns is the same as that described in Example 1 above, and will not be repeated here.

[0048] In this comparative example, the POY oiling agent formulation for reducing stiff nylon 6 high-elasticity yarns described above was used, and the spinning steps were the same as those described in Example 1 above, and will not be repeated here.

[0049] In this comparative example, the untwisting tension of the produced yarn after texturing was 18-25 CN. The degradation rate of DTY stiff yarns after quality testing was as high as 3.3%. Compared with Comparative Example 1, the reduction in smoothing agent content significantly reduced the degradation rate of stiff yarns, confirming that changing the oiling agent formulation can reduce the small stiff yarn defects caused by slippage and vibration during texturing. Furthermore, the smoothing agent ratio of 40% was found to be the critical ratio for eliminating stiff yarns. Physical property tests showed that the breaking strength, breaking elongation, evenness, and boiling water shrinkage of the obtained nylon 6 fiber all met the requirements of GB / T16603-2008 "Nylon Elastic Yarn" and satisfied the requirements for post-processing and use.

[0050] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A POY oiling agent formulation for reducing stiffness in nylon 6 high-elasticity yarn, characterized in that, It contains the following components by weight percentage: smoothing agent 35-40%, emulsifier 20-24%, antistatic agent 3%, softening agent 19-20%, and other additives 18%.

2. The POY oiling agent formulation for reducing stiffness in nylon 6 high-elasticity yarn as described in claim 1, characterized in that, The smoothing agent is a pentaerythritol fatty acid ester.

3. The POY oiling agent formulation for reducing stiffness in nylon 6 high-elasticity yarn as described in claim 1, characterized in that, The emulsifier is fatty alcohol polyoxyethylene ether.

4. The POY oiling agent formulation for reducing stiffness in nylon 6 high-elasticity yarn as described in claim 1, characterized in that, The antistatic agent is a polyether phosphate salt.

5. The POY oiling agent formulation for reducing stiffness in nylon 6 high-elasticity yarn as described in claim 1, characterized in that, The softening agent is softener SG.

6. Apply the POY oiling agent formulation for reducing small stiff fibers in nylon 6 high-elasticity yarn as described in claim 1 to the production of nylon 6 high-elasticity yarn.

7. A method for producing nylon 6 high-elasticity yarn, characterized in that, Specifically, the following steps are included: (1) Polycaprolactam chips were melted and spun using a screw extruder to obtain POY 85D / 24F precursor yarn; (2) In the POY oiling process, the POY oil formulation as described in claim 1 is used, and the oiling process is carried out through two wet oiling systems, and the oiling rate is controlled. (3) The oil-containing POY is texturized by the high elastic yarn texturizing machine, and after passing through the filament cutter, it enters the first roller, then passes through the heating box and is false twisted in the false twister. After passing through the second roller, it enters the second heating box, and finally is wound by the winding tension. The draw ratio and twist ratio are adjusted, and the untwisting tension is controlled to be 26-28 CN to obtain high elastic yarn 70 D / 24 F. (4) The high elastic yarn 70 D / 24 F was subjected to quality inspection to determine the rate of degradation of small stiff yarns in the high elastic yarn.

8. The method for producing nylon 6 high-elasticity yarn as described in claim 7, characterized in that, In step (2), the oiling rate is controlled to be 0.6% ± 0.1%.

9. The method for producing nylon 6 high-elasticity yarn as described in claim 7, characterized in that, The temperature of the false twister in step (3) is 168°C; the stretch ratio is 1.25; and the twist ratio is 1.62.

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